1. Field of the Invention
The present invention relates to a display element, portable equipment, and an imaging device which have high portability, a high compactifying capability, and high operability.
2. Description of the Related Art
Numerous kinds of portable equipment using flexible display elements which can be reduced in size when carried have been proposed. For example, like a roll-up display disclosed in Japanese Patent Application Laid-Open No. H09-216465, some kinds of portable equipment enable viewing of images recorded by thermal heads. According to Japanese Patent Application Laid-Open No. H09-216465, a recording medium pulled out of the main body of equipment is flexible like paper and does not have flatness alone. Therefore, as is evident from the drawings of Japanese Patent Application Laid-Open No. H09-216465, according to the characteristics, the recording medium has to be held with both hands to keep the flatness.
As disclosed in Japanese Patent Application Laid-Open No. 2003-250074 and Japanese Patent Application Laid-Open No. 2003-274250, some kinds of portable equipment have flexible displays and have the following drawbacks: when the strength of a display is increased to keep the shape of the display pulled out of the main body of equipment, the strength becomes a resistance to rolling when the display is stored. Thus it is difficult to roll up the display. On the other hand, when the flexibility of the display is increased to facilitate rolling, the shape retention of the display decreases. In order to keep the flatness, it is necessary to hold a gripping portion on the opposite side of the main body of equipment, thus operability is hard to obtain.
Further, Japanese Patent Application Laid-Open No. 2000-19980 proposes a display body that is curved when pulled out (claim 1 and paragraph [0022] in Japanese Patent Application Laid-Open No. 2000-19980). A small curvature causes an insufficient strength and the curvature has to be increased to obtain a sufficient strength. As a result, a curved display may be viewed and the display may not have a designed aspect ratio.
Furthermore, Japanese Patent Application Laid-Open No. 2000-10086 and Japanese Patent Application Laid-Open No. H09-134132 propose display units that are surrounded by frames keeping the flatness of the display units. Since the frames cannot be rolled up, a problem arises in storing the frames. Thus such equipment is stored in a complicated manner and the size reduction is limited.
In Japanese Patent Application Laid-Open No. 2004-118803 and Japanese Patent Application Laid-Open No. 2004-109382, displays are just foldable and thus the degree of size reduction is smaller than that of a roll-up display.
As described above, in related art, numerous kinds of equipment using flexible display elements are proposed which are reduced in size when carried. However, all of the methods are defective in ease of rolling (compactifying capability) and retention of flatness (operability) during periods of use.